/*
 * File:         bf5xx_sport.c
 * Based on:
 * Author:       Roy Huang <roy.huang@analog.com>
 *
 * Created:      Tue Sep 21 10:52:42 CEST 2004
 * Description:
 *               Blackfin SPORT Driver
 *
 *               Copyright 2004-2007 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/gpio.h>
#include <linux/bug.h>
#include <asm/portmux.h>
#include <asm/dma.h>
#include <asm/blackfin.h>
#include <asm/cacheflush.h>

#include "bf5xx-sport.h"
/* delay between frame sync pulse and first data bit in multichannel mode */
#define FRAME_DELAY (1<<12)

struct sport_device *sport_handle;
EXPORT_SYMBOL(sport_handle);
/* note: multichannel is in units of 8 channels,
 * tdm_count is # channels NOT / 8 ! */
int sport_set_multichannel(struct sport_device *sport,
                int tdm_count, u32 mask, int packed)
{
        pr_debug("%s tdm_count=%d mask:0x%08x packed=%d\n", __func__,
                        tdm_count, mask, packed);

        if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
                return -EBUSY;

        if (tdm_count & 0x7)
                return -EINVAL;

        if (tdm_count > 32)
                return -EINVAL; /* Only support less than 32 channels now */

        if (tdm_count) {
                sport->regs->mcmc1 = ((tdm_count>>3)-1) << 12;
                sport->regs->mcmc2 = FRAME_DELAY | MCMEN | \
                                (packed ? (MCDTXPE|MCDRXPE) : 0);

                sport->regs->mtcs0 = mask;
                sport->regs->mrcs0 = mask;
                sport->regs->mtcs1 = 0;
                sport->regs->mrcs1 = 0;
                sport->regs->mtcs2 = 0;
                sport->regs->mrcs2 = 0;
                sport->regs->mtcs3 = 0;
                sport->regs->mrcs3 = 0;
        } else {
                sport->regs->mcmc1 = 0;
                sport->regs->mcmc2 = 0;

                sport->regs->mtcs0 = 0;
                sport->regs->mrcs0 = 0;
        }

        sport->regs->mtcs1 = 0; sport->regs->mtcs2 = 0; sport->regs->mtcs3 = 0;
        sport->regs->mrcs1 = 0; sport->regs->mrcs2 = 0; sport->regs->mrcs3 = 0;

        SSYNC();

        return 0;
}
EXPORT_SYMBOL(sport_set_multichannel);

int sport_config_rx(struct sport_device *sport, unsigned int rcr1,
                unsigned int rcr2, unsigned int clkdiv, unsigned int fsdiv)
{
        if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
                return -EBUSY;

        sport->regs->rcr1 = rcr1;
        sport->regs->rcr2 = rcr2;
        sport->regs->rclkdiv = clkdiv;
        sport->regs->rfsdiv = fsdiv;

        SSYNC();

        return 0;
}
EXPORT_SYMBOL(sport_config_rx);

int sport_config_tx(struct sport_device *sport, unsigned int tcr1,
                unsigned int tcr2, unsigned int clkdiv, unsigned int fsdiv)
{
        if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
                return -EBUSY;

        sport->regs->tcr1 = tcr1;
        sport->regs->tcr2 = tcr2;
        sport->regs->tclkdiv = clkdiv;
        sport->regs->tfsdiv = fsdiv;

        SSYNC();

        return 0;
}
EXPORT_SYMBOL(sport_config_tx);

static void setup_desc(struct dmasg *desc, void *buf, int fragcount,
                size_t fragsize, unsigned int cfg,
                unsigned int x_count, unsigned int ycount, size_t wdsize)
{

        int i;

        for (i = 0; i < fragcount; ++i) {
                desc[i].next_desc_addr  = &(desc[i + 1]);
                desc[i].start_addr = (unsigned long)buf + i*fragsize;
                desc[i].cfg = cfg;
                desc[i].x_count = x_count;
                desc[i].x_modify = wdsize;
                desc[i].y_count = ycount;
                desc[i].y_modify = wdsize;
        }

        /* make circular */
        desc[fragcount-1].next_desc_addr = desc;

        pr_debug("setup desc: desc0=%p, next0=%p, desc1=%p,"
                "next1=%p\nx_count=%x,y_count=%x,addr=0x%lx,cfs=0x%x\n",
                desc, desc[0].next_desc_addr,
                desc+1, desc[1].next_desc_addr,
                desc[0].x_count, desc[0].y_count,
                desc[0].start_addr, desc[0].cfg);
}

static int sport_start(struct sport_device *sport)
{
        enable_dma(sport->dma_rx_chan);
        enable_dma(sport->dma_tx_chan);
        sport->regs->rcr1 |= RSPEN;
        sport->regs->tcr1 |= TSPEN;
        SSYNC();

        return 0;
}

static int sport_stop(struct sport_device *sport)
{
        sport->regs->tcr1 &= ~TSPEN;
        sport->regs->rcr1 &= ~RSPEN;
        SSYNC();

        disable_dma(sport->dma_rx_chan);
        disable_dma(sport->dma_tx_chan);
        return 0;
}

static inline int sport_hook_rx_dummy(struct sport_device *sport)
{
        struct dmasg *desc, temp_desc;
        unsigned long flags;

        BUG_ON(sport->dummy_rx_desc == NULL);
        BUG_ON(sport->curr_rx_desc == sport->dummy_rx_desc);

        /* Maybe the dummy buffer descriptor ring is damaged */
        sport->dummy_rx_desc->next_desc_addr = sport->dummy_rx_desc + 1;

        local_irq_save(flags);
        desc = get_dma_next_desc_ptr(sport->dma_rx_chan);
        /* Copy the descriptor which will be damaged to backup */
        temp_desc = *desc;
        desc->x_count = sport->dummy_count / 2;
        desc->y_count = 0;
        desc->next_desc_addr = sport->dummy_rx_desc;
        local_irq_restore(flags);
        /* Waiting for dummy buffer descriptor is already hooked*/
        while ((get_dma_curr_desc_ptr(sport->dma_rx_chan) -
                        sizeof(struct dmasg)) != sport->dummy_rx_desc)
                continue;
        sport->curr_rx_desc = sport->dummy_rx_desc;
        /* Restore the damaged descriptor */
        *desc = temp_desc;

        return 0;
}

static inline int sport_rx_dma_start(struct sport_device *sport, int dummy)
{
        if (dummy) {
                sport->dummy_rx_desc->next_desc_addr = sport->dummy_rx_desc;
                sport->curr_rx_desc = sport->dummy_rx_desc;
        } else
                sport->curr_rx_desc = sport->dma_rx_desc;

        set_dma_next_desc_addr(sport->dma_rx_chan, sport->curr_rx_desc);
        set_dma_x_count(sport->dma_rx_chan, 0);
        set_dma_x_modify(sport->dma_rx_chan, 0);
        set_dma_config(sport->dma_rx_chan, (DMAFLOW_LARGE | NDSIZE_9 | \
                                WDSIZE_32 | WNR));
        set_dma_curr_addr(sport->dma_rx_chan, sport->curr_rx_desc->start_addr);
        SSYNC();

        return 0;
}

static inline int sport_tx_dma_start(struct sport_device *sport, int dummy)
{
        if (dummy) {
                sport->dummy_tx_desc->next_desc_addr = sport->dummy_tx_desc;
                sport->curr_tx_desc = sport->dummy_tx_desc;
        } else
                sport->curr_tx_desc = sport->dma_tx_desc;

        set_dma_next_desc_addr(sport->dma_tx_chan, sport->curr_tx_desc);
        set_dma_x_count(sport->dma_tx_chan, 0);
        set_dma_x_modify(sport->dma_tx_chan, 0);
        set_dma_config(sport->dma_tx_chan,
                        (DMAFLOW_LARGE | NDSIZE_9 | WDSIZE_32));
        set_dma_curr_addr(sport->dma_tx_chan, sport->curr_tx_desc->start_addr);
        SSYNC();

        return 0;
}

int sport_rx_start(struct sport_device *sport)
{
        unsigned long flags;
        pr_debug("%s enter\n", __func__);
        if (sport->rx_run)
                return -EBUSY;
        if (sport->tx_run) {
                /* tx is running, rx is not running */
                BUG_ON(sport->dma_rx_desc == NULL);
                BUG_ON(sport->curr_rx_desc != sport->dummy_rx_desc);
                local_irq_save(flags);
                while ((get_dma_curr_desc_ptr(sport->dma_rx_chan) -
                        sizeof(struct dmasg)) != sport->dummy_rx_desc)
                        continue;
                sport->dummy_rx_desc->next_desc_addr = sport->dma_rx_desc;
                local_irq_restore(flags);
                sport->curr_rx_desc = sport->dma_rx_desc;
        } else {
                sport_tx_dma_start(sport, 1);
                sport_rx_dma_start(sport, 0);
                sport_start(sport);
        }

        sport->rx_run = 1;

        return 0;
}
EXPORT_SYMBOL(sport_rx_start);

int sport_rx_stop(struct sport_device *sport)
{
        pr_debug("%s enter\n", __func__);

        if (!sport->rx_run)
                return 0;
        if (sport->tx_run) {
                /* TX dma is still running, hook the dummy buffer */
                sport_hook_rx_dummy(sport);
        } else {
                /* Both rx and tx dma will be stopped */
                sport_stop(sport);
                sport->curr_rx_desc = NULL;
                sport->curr_tx_desc = NULL;
        }

        sport->rx_run = 0;

        return 0;
}
EXPORT_SYMBOL(sport_rx_stop);

static inline int sport_hook_tx_dummy(struct sport_device *sport)
{
        struct dmasg *desc, temp_desc;
        unsigned long flags;

        BUG_ON(sport->dummy_tx_desc == NULL);
        BUG_ON(sport->curr_tx_desc == sport->dummy_tx_desc);

        sport->dummy_tx_desc->next_desc_addr = sport->dummy_tx_desc + 1;

        /* Shorten the time on last normal descriptor */
        local_irq_save(flags);
        desc = get_dma_next_desc_ptr(sport->dma_tx_chan);
        /* Store the descriptor which will be damaged */
        temp_desc = *desc;
        desc->x_count = sport->dummy_count / 2;
        desc->y_count = 0;
        desc->next_desc_addr = sport->dummy_tx_desc;
        local_irq_restore(flags);
        /* Waiting for dummy buffer descriptor is already hooked*/
        while ((get_dma_curr_desc_ptr(sport->dma_tx_chan) - \
                        sizeof(struct dmasg)) != sport->dummy_tx_desc)
                continue;
        sport->curr_tx_desc = sport->dummy_tx_desc;
        /* Restore the damaged descriptor */
        *desc = temp_desc;

        return 0;
}

int sport_tx_start(struct sport_device *sport)
{
        unsigned long flags;
        pr_debug("%s: tx_run:%d, rx_run:%d\n", __func__,
                        sport->tx_run, sport->rx_run);
        if (sport->tx_run)
                return -EBUSY;
        if (sport->rx_run) {
                BUG_ON(sport->dma_tx_desc == NULL);
                BUG_ON(sport->curr_tx_desc != sport->dummy_tx_desc);
                /* Hook the normal buffer descriptor */
                local_irq_save(flags);
                while ((get_dma_curr_desc_ptr(sport->dma_tx_chan) -
                        sizeof(struct dmasg)) != sport->dummy_tx_desc)
                        continue;
                sport->dummy_tx_desc->next_desc_addr = sport->dma_tx_desc;
                local_irq_restore(flags);
                sport->curr_tx_desc = sport->dma_tx_desc;
        } else {

                sport_tx_dma_start(sport, 0);
                /* Let rx dma run the dummy buffer */
                sport_rx_dma_start(sport, 1);
                sport_start(sport);
        }
        sport->tx_run = 1;
        return 0;
}
EXPORT_SYMBOL(sport_tx_start);

int sport_tx_stop(struct sport_device *sport)
{
        if (!sport->tx_run)
                return 0;
        if (sport->rx_run) {
                /* RX is still running, hook the dummy buffer */
                sport_hook_tx_dummy(sport);
        } else {
                /* Both rx and tx dma stopped */
                sport_stop(sport);
                sport->curr_rx_desc = NULL;
                sport->curr_tx_desc = NULL;
        }

        sport->tx_run = 0;

        return 0;
}
EXPORT_SYMBOL(sport_tx_stop);

static inline int compute_wdsize(size_t wdsize)
{
        switch (wdsize) {
        case 1:
                return WDSIZE_8;
        case 2:
                return WDSIZE_16;
        case 4:
        default:
                return WDSIZE_32;
        }
}

int sport_config_rx_dma(struct sport_device *sport, void *buf,
                int fragcount, size_t fragsize)
{
        unsigned int x_count;
        unsigned int y_count;
        unsigned int cfg;
        dma_addr_t addr;

        pr_debug("%s buf:%p, frag:%d, fragsize:0x%lx\n", __func__, \
                        buf, fragcount, fragsize);

        x_count = fragsize / sport->wdsize;
        y_count = 0;

        /* for fragments larger than 64k words we use 2d dma,
         * denote fragecount as two numbers' mutliply and both of them
         * are less than 64k.*/
        if (x_count >= 0x10000) {
                int i, count = x_count;

                for (i = 16; i > 0; i--) {
                        x_count = 1 << i;
                        if ((count & (x_count - 1)) == 0) {
                                y_count = count >> i;
                                if (y_count < 0x10000)
                                        break;
                        }
                }
                if (i == 0)
                        return -EINVAL;
        }
        pr_debug("%s(x_count:0x%x, y_count:0x%x)\n", __func__,
                        x_count, y_count);

        if (sport->dma_rx_desc)
                dma_free_coherent(NULL, sport->rx_desc_bytes,
                                        sport->dma_rx_desc, 0);

        /* Allocate a new descritor ring as current one. */
        sport->dma_rx_desc = dma_alloc_coherent(NULL, \
                        fragcount * sizeof(struct dmasg), &addr, 0);
        sport->rx_desc_bytes = fragcount * sizeof(struct dmasg);

        if (!sport->dma_rx_desc) {
                pr_err("Failed to allocate memory for rx desc\n");
                return -ENOMEM;
        }

        sport->rx_buf = buf;
        sport->rx_fragsize = fragsize;
        sport->rx_frags = fragcount;

        cfg     = 0x7000 | DI_EN | compute_wdsize(sport->wdsize) | WNR | \
                  (DESC_ELEMENT_COUNT << 8); /* large descriptor mode */

        if (y_count != 0)
                cfg |= DMA2D;

        setup_desc(sport->dma_rx_desc, buf, fragcount, fragsize,
                        cfg|DMAEN, x_count, y_count, sport->wdsize);

        return 0;
}
EXPORT_SYMBOL(sport_config_rx_dma);

int sport_config_tx_dma(struct sport_device *sport, void *buf, \
                int fragcount, size_t fragsize)
{
        unsigned int x_count;
        unsigned int y_count;
        unsigned int cfg;
        dma_addr_t addr;

        pr_debug("%s buf:%p, fragcount:%d, fragsize:0x%lx\n",
                        __func__, buf, fragcount, fragsize);

        x_count = fragsize/sport->wdsize;
        y_count = 0;

        /* for fragments larger than 64k words we use 2d dma,
         * denote fragecount as two numbers' mutliply and both of them
         * are less than 64k.*/
        if (x_count >= 0x10000) {
                int i, count = x_count;

                for (i = 16; i > 0; i--) {
                        x_count = 1 << i;
                        if ((count & (x_count - 1)) == 0) {
                                y_count = count >> i;
                                if (y_count < 0x10000)
                                        break;
                        }
                }
                if (i == 0)
                        return -EINVAL;
        }
        pr_debug("%s x_count:0x%x, y_count:0x%x\n", __func__,
                        x_count, y_count);


        if (sport->dma_tx_desc) {
                dma_free_coherent(NULL, sport->tx_desc_bytes, \
                                sport->dma_tx_desc, 0);
        }

        sport->dma_tx_desc = dma_alloc_coherent(NULL, \
                        fragcount * sizeof(struct dmasg), &addr, 0);
        sport->tx_desc_bytes = fragcount * sizeof(struct dmasg);
        if (!sport->dma_tx_desc) {
                pr_err("Failed to allocate memory for tx desc\n");
                return -ENOMEM;
        }

        sport->tx_buf = buf;
        sport->tx_fragsize = fragsize;
        sport->tx_frags = fragcount;
        cfg     = 0x7000 | DI_EN | compute_wdsize(sport->wdsize) | \
                  (DESC_ELEMENT_COUNT << 8); /* large descriptor mode */

        if (y_count != 0)
                cfg |= DMA2D;

        setup_desc(sport->dma_tx_desc, buf, fragcount, fragsize,
                        cfg|DMAEN, x_count, y_count, sport->wdsize);

        return 0;
}
EXPORT_SYMBOL(sport_config_tx_dma);

/* setup dummy dma descriptor ring, which don't generate interrupts,
 * the x_modify is set to 0 */
static int sport_config_rx_dummy(struct sport_device *sport)
{
        struct dmasg *desc;
        unsigned config;

        pr_debug("%s entered\n", __func__);
        if (L1_DATA_A_LENGTH)
                desc = l1_data_sram_zalloc(2 * sizeof(*desc));
        else {
                dma_addr_t addr;
                desc = dma_alloc_coherent(NULL, 2 * sizeof(*desc), &addr, 0);
                memset(desc, 0, 2 * sizeof(*desc));
        }
        if (desc == NULL) {
                pr_err("Failed to allocate memory for dummy rx desc\n");
                return -ENOMEM;
        }
        sport->dummy_rx_desc = desc;
        desc->start_addr = (unsigned long)sport->dummy_buf;
        config = DMAFLOW_LARGE | NDSIZE_9 | compute_wdsize(sport->wdsize)
                 | WNR | DMAEN;
        desc->cfg = config;
        desc->x_count = sport->dummy_count/sport->wdsize;
        desc->x_modify = sport->wdsize;
        desc->y_count = 0;
        desc->y_modify = 0;
        memcpy(desc+1, desc, sizeof(*desc));
        desc->next_desc_addr = desc + 1;
        desc[1].next_desc_addr = desc;
        return 0;
}

static int sport_config_tx_dummy(struct sport_device *sport)
{
        struct dmasg *desc;
        unsigned int config;

        pr_debug("%s entered\n", __func__);

        if (L1_DATA_A_LENGTH)
                desc = l1_data_sram_zalloc(2 * sizeof(*desc));
        else {
                dma_addr_t addr;
                desc = dma_alloc_coherent(NULL, 2 * sizeof(*desc), &addr, 0);
                memset(desc, 0, 2 * sizeof(*desc));
        }
        if (!desc) {
                pr_err("Failed to allocate memory for dummy tx desc\n");
                return -ENOMEM;
        }
        sport->dummy_tx_desc = desc;
        desc->start_addr = (unsigned long)sport->dummy_buf + \
                sport->dummy_count;
        config = DMAFLOW_LARGE | NDSIZE_9 |
                 compute_wdsize(sport->wdsize) | DMAEN;
        desc->cfg = config;
        desc->x_count = sport->dummy_count/sport->wdsize;
        desc->x_modify = sport->wdsize;
        desc->y_count = 0;
        desc->y_modify = 0;
        memcpy(desc+1, desc, sizeof(*desc));
        desc->next_desc_addr = desc + 1;
        desc[1].next_desc_addr = desc;
        return 0;
}

unsigned long sport_curr_offset_rx(struct sport_device *sport)
{
        unsigned long curr = get_dma_curr_addr(sport->dma_rx_chan);

        return (unsigned char *)curr - sport->rx_buf;
}
EXPORT_SYMBOL(sport_curr_offset_rx);

unsigned long sport_curr_offset_tx(struct sport_device *sport)
{
        unsigned long curr = get_dma_curr_addr(sport->dma_tx_chan);

        return (unsigned char *)curr - sport->tx_buf;
}
EXPORT_SYMBOL(sport_curr_offset_tx);

void sport_incfrag(struct sport_device *sport, int *frag, int tx)
{
        ++(*frag);
        if (tx == 1 && *frag == sport->tx_frags)
                *frag = 0;

        if (tx == 0 && *frag == sport->rx_frags)
                *frag = 0;
}
EXPORT_SYMBOL(sport_incfrag);

void sport_decfrag(struct sport_device *sport, int *frag, int tx)
{
        --(*frag);
        if (tx == 1 && *frag == 0)
                *frag = sport->tx_frags;

        if (tx == 0 && *frag == 0)
                *frag = sport->rx_frags;
}
EXPORT_SYMBOL(sport_decfrag);

static int sport_check_status(struct sport_device *sport,
                unsigned int *sport_stat,
                unsigned int *rx_stat,
                unsigned int *tx_stat)
{
        int status = 0;

        if (sport_stat) {
                SSYNC();
                status = sport->regs->stat;
                if (status & (TOVF|TUVF|ROVF|RUVF))
                        sport->regs->stat = (status & (TOVF|TUVF|ROVF|RUVF));
                SSYNC();
                *sport_stat = status;
        }

        if (rx_stat) {
                SSYNC();
                status = get_dma_curr_irqstat(sport->dma_rx_chan);
                if (status & (DMA_DONE|DMA_ERR))
                        clear_dma_irqstat(sport->dma_rx_chan);
                SSYNC();
                *rx_stat = status;
        }

        if (tx_stat) {
                SSYNC();
                status = get_dma_curr_irqstat(sport->dma_tx_chan);
                if (status & (DMA_DONE|DMA_ERR))
                        clear_dma_irqstat(sport->dma_tx_chan);
                SSYNC();
                *tx_stat = status;
        }

        return 0;
}

int  sport_dump_stat(struct sport_device *sport, char *buf, size_t len)
{
        int ret;

        ret = snprintf(buf, len,
                        "sts: 0x%04x\n"
                        "rx dma %d sts: 0x%04x tx dma %d sts: 0x%04x\n",
                        sport->regs->stat,
                        sport->dma_rx_chan,
                        get_dma_curr_irqstat(sport->dma_rx_chan),
                        sport->dma_tx_chan,
                        get_dma_curr_irqstat(sport->dma_tx_chan));
        buf += ret;
        len -= ret;

        ret += snprintf(buf, len,
                        "curr_rx_desc:0x%p, curr_tx_desc:0x%p\n"
                        "dma_rx_desc:0x%p, dma_tx_desc:0x%p\n"
                        "dummy_rx_desc:0x%p, dummy_tx_desc:0x%p\n",
                        sport->curr_rx_desc, sport->curr_tx_desc,
                        sport->dma_rx_desc, sport->dma_tx_desc,
                        sport->dummy_rx_desc, sport->dummy_tx_desc);

        return ret;
}

static irqreturn_t rx_handler(int irq, void *dev_id)
{
        unsigned int rx_stat;
        struct sport_device *sport = dev_id;

        pr_debug("%s enter\n", __func__);
        sport_check_status(sport, NULL, &rx_stat, NULL);
        if (!(rx_stat & DMA_DONE))
                pr_err("rx dma is already stopped\n");

        if (sport->rx_callback) {
                sport->rx_callback(sport->rx_data);
                return IRQ_HANDLED;
        }

        return IRQ_NONE;
}

static irqreturn_t tx_handler(int irq, void *dev_id)
{
        unsigned int tx_stat;
        struct sport_device *sport = dev_id;
        pr_debug("%s enter\n", __func__);
        sport_check_status(sport, NULL, NULL, &tx_stat);
        if (!(tx_stat & DMA_DONE)) {
                pr_err("tx dma is already stopped\n");
                return IRQ_HANDLED;
        }
        if (sport->tx_callback) {
                sport->tx_callback(sport->tx_data);
                return IRQ_HANDLED;
        }

        return IRQ_NONE;
}

static irqreturn_t err_handler(int irq, void *dev_id)
{
        unsigned int status = 0;
        struct sport_device *sport = dev_id;

        pr_debug("%s\n", __func__);
        if (sport_check_status(sport, &status, NULL, NULL)) {
                pr_err("error checking status ??");
                return IRQ_NONE;
        }

        if (status & (TOVF|TUVF|ROVF|RUVF)) {
                pr_info("sport status error:%s%s%s%s\n",
                                status & TOVF ? " TOVF" : "",
                                status & TUVF ? " TUVF" : "",
                                status & ROVF ? " ROVF" : "",
                                status & RUVF ? " RUVF" : "");
                if (status & TOVF || status & TUVF) {
                        disable_dma(sport->dma_tx_chan);
                        if (sport->tx_run)
                                sport_tx_dma_start(sport, 0);
                        else
                                sport_tx_dma_start(sport, 1);
                        enable_dma(sport->dma_tx_chan);
                } else {
                        disable_dma(sport->dma_rx_chan);
                        if (sport->rx_run)
                                sport_rx_dma_start(sport, 0);
                        else
                                sport_rx_dma_start(sport, 1);
                        enable_dma(sport->dma_rx_chan);
                }
        }
        status = sport->regs->stat;
        if (status & (TOVF|TUVF|ROVF|RUVF))
                sport->regs->stat = (status & (TOVF|TUVF|ROVF|RUVF));
        SSYNC();

        if (sport->err_callback)
                sport->err_callback(sport->err_data);

        return IRQ_HANDLED;
}

int sport_set_rx_callback(struct sport_device *sport,
                       void (*rx_callback)(void *), void *rx_data)
{
        BUG_ON(rx_callback == NULL);
        sport->rx_callback = rx_callback;
        sport->rx_data = rx_data;

        return 0;
}
EXPORT_SYMBOL(sport_set_rx_callback);

int sport_set_tx_callback(struct sport_device *sport,
                void (*tx_callback)(void *), void *tx_data)
{
        BUG_ON(tx_callback == NULL);
        sport->tx_callback = tx_callback;
        sport->tx_data = tx_data;

        return 0;
}
EXPORT_SYMBOL(sport_set_tx_callback);

int sport_set_err_callback(struct sport_device *sport,
                void (*err_callback)(void *), void *err_data)
{
        BUG_ON(err_callback == NULL);
        sport->err_callback = err_callback;
        sport->err_data = err_data;

        return 0;
}
EXPORT_SYMBOL(sport_set_err_callback);

struct sport_device *sport_init(struct sport_param *param, unsigned wdsize,
                unsigned dummy_count, void *private_data)
{
        int ret;
        struct sport_device *sport;
        pr_debug("%s enter\n", __func__);
        BUG_ON(param == NULL);
        BUG_ON(wdsize == 0 || dummy_count == 0);
        sport = kmalloc(sizeof(struct sport_device), GFP_KERNEL);
        if (!sport) {
                pr_err("Failed to allocate for sport device\n");
                return NULL;
        }

        memset(sport, 0, sizeof(struct sport_device));
        sport->dma_rx_chan = param->dma_rx_chan;
        sport->dma_tx_chan = param->dma_tx_chan;
        sport->err_irq = param->err_irq;
        sport->regs = param->regs;
        sport->private_data = private_data;

        if (request_dma(sport->dma_rx_chan, "SPORT RX Data") == -EBUSY) {
                pr_err("Failed to request RX dma %d\n", \
                                sport->dma_rx_chan);
                goto __init_err1;
        }
        if (set_dma_callback(sport->dma_rx_chan, rx_handler, sport) != 0) {
                pr_err("Failed to request RX irq %d\n", \
                                sport->dma_rx_chan);
                goto __init_err2;
        }

        if (request_dma(sport->dma_tx_chan, "SPORT TX Data") == -EBUSY) {
                pr_err("Failed to request TX dma %d\n", \
                                sport->dma_tx_chan);
                goto __init_err2;
        }

        if (set_dma_callback(sport->dma_tx_chan, tx_handler, sport) != 0) {
                pr_err("Failed to request TX irq %d\n", \
                                sport->dma_tx_chan);
                goto __init_err3;
        }

        if (request_irq(sport->err_irq, err_handler, IRQF_SHARED, "SPORT err",
                        sport) < 0) {
                pr_err("Failed to request err irq:%d\n", \
                                sport->err_irq);
                goto __init_err3;
        }

        pr_err("dma rx:%d tx:%d, err irq:%d, regs:%p\n",
                        sport->dma_rx_chan, sport->dma_tx_chan,
                        sport->err_irq, sport->regs);

        sport->wdsize = wdsize;
        sport->dummy_count = dummy_count;

        if (L1_DATA_A_LENGTH)
                sport->dummy_buf = l1_data_sram_zalloc(dummy_count * 2);
        else
                sport->dummy_buf = kzalloc(dummy_count * 2, GFP_KERNEL);
        if (sport->dummy_buf == NULL) {
                pr_err("Failed to allocate dummy buffer\n");
                goto __error;
        }

        ret = sport_config_rx_dummy(sport);
        if (ret) {
                pr_err("Failed to config rx dummy ring\n");
                goto __error;
        }
        ret = sport_config_tx_dummy(sport);
        if (ret) {
                pr_err("Failed to config tx dummy ring\n");
                goto __error;
        }

        return sport;
__error:
        free_irq(sport->err_irq, sport);
__init_err3:
        free_dma(sport->dma_tx_chan);
__init_err2:
        free_dma(sport->dma_rx_chan);
__init_err1:
        kfree(sport);
        return NULL;
}
EXPORT_SYMBOL(sport_init);

void sport_done(struct sport_device *sport)
{
        if (sport == NULL)
                return;

        sport_stop(sport);
        if (sport->dma_rx_desc)
                dma_free_coherent(NULL, sport->rx_desc_bytes,
                        sport->dma_rx_desc, 0);
        if (sport->dma_tx_desc)
                dma_free_coherent(NULL, sport->tx_desc_bytes,
                        sport->dma_tx_desc, 0);

#if L1_DATA_A_LENGTH != 0
        l1_data_sram_free(sport->dummy_rx_desc);
        l1_data_sram_free(sport->dummy_tx_desc);
        l1_data_sram_free(sport->dummy_buf);
#else
        dma_free_coherent(NULL, 2*sizeof(struct dmasg),
                sport->dummy_rx_desc, 0);
        dma_free_coherent(NULL, 2*sizeof(struct dmasg),
                sport->dummy_tx_desc, 0);
        kfree(sport->dummy_buf);
#endif
        free_dma(sport->dma_rx_chan);
        free_dma(sport->dma_tx_chan);
        free_irq(sport->err_irq, sport);

        kfree(sport);
                sport = NULL;
}
EXPORT_SYMBOL(sport_done);

/*
* It is only used to send several bytes when dma is not enabled
 * sport controller is configured but not enabled.
 * Multichannel cannot works with pio mode */
/* Used by ac97 to write and read codec register */
int sport_send_and_recv(struct sport_device *sport, u8 *out_data, \
                u8 *in_data, int len)
{
        unsigned short dma_config;
        unsigned short status;
        unsigned long flags;
        unsigned long wait = 0;

        pr_debug("%s enter, out_data:%p, in_data:%p len:%d\n", \
                        __func__, out_data, in_data, len);
        pr_debug("tcr1:0x%04x, tcr2:0x%04x, tclkdiv:0x%04x, tfsdiv:0x%04x\n"
                        "mcmc1:0x%04x, mcmc2:0x%04x\n",
                        sport->regs->tcr1, sport->regs->tcr2,
                        sport->regs->tclkdiv, sport->regs->tfsdiv,
                        sport->regs->mcmc1, sport->regs->mcmc2);
        flush_dcache_range((unsigned)out_data, (unsigned)(out_data + len));

        /* Enable tx dma */
        dma_config = (RESTART | WDSIZE_16 | DI_EN);
        set_dma_start_addr(sport->dma_tx_chan, (unsigned long)out_data);
        set_dma_x_count(sport->dma_tx_chan, len/2);
        set_dma_x_modify(sport->dma_tx_chan, 2);
        set_dma_config(sport->dma_tx_chan, dma_config);
        enable_dma(sport->dma_tx_chan);

        if (in_data != NULL) {
                invalidate_dcache_range((unsigned)in_data, \
                                (unsigned)(in_data + len));
                /* Enable rx dma */
                dma_config = (RESTART | WDSIZE_16 | WNR | DI_EN);
                set_dma_start_addr(sport->dma_rx_chan, (unsigned long)in_data);
                set_dma_x_count(sport->dma_rx_chan, len/2);
                set_dma_x_modify(sport->dma_rx_chan, 2);
                set_dma_config(sport->dma_rx_chan, dma_config);
                enable_dma(sport->dma_rx_chan);
        }

        local_irq_save(flags);
        sport->regs->tcr1 |= TSPEN;
        sport->regs->rcr1 |= RSPEN;
        SSYNC();

        status = get_dma_curr_irqstat(sport->dma_tx_chan);
        while (status & DMA_RUN) {
                udelay(1);
                status = get_dma_curr_irqstat(sport->dma_tx_chan);
                pr_debug("DMA status:0x%04x\n", status);
                if (wait++ > 100)
                        goto __over;
        }
        status = sport->regs->stat;
        wait = 0;

        while (!(status & TXHRE)) {
                pr_debug("sport status:0x%04x\n", status);
                udelay(1);
                status = *(unsigned short *)&sport->regs->stat;
                if (wait++ > 1000)
                        goto __over;
        }
        /* Wait for the last byte sent out */
        udelay(20);
        pr_debug("sport status:0x%04x\n", status);

__over:
        sport->regs->tcr1 &= ~TSPEN;
        sport->regs->rcr1 &= ~RSPEN;
        SSYNC();
        disable_dma(sport->dma_tx_chan);
        /* Clear the status */
        clear_dma_irqstat(sport->dma_tx_chan);

        if (in_data != NULL) {
                disable_dma(sport->dma_rx_chan);
                clear_dma_irqstat(sport->dma_rx_chan);
        }
        SSYNC();
        local_irq_restore(flags);

        return 0;
}
EXPORT_SYMBOL(sport_send_and_recv);

MODULE_AUTHOR("Roy Huang");
MODULE_DESCRIPTION("SPORT driver for ADI Blackfin");
MODULE_LICENSE("GPL");